Reports came via Google Groups that clicking the terms of service link did not work for everyone.

When I click on I understand the terms of service, it just cycles back to the TOS again and I can't get to my stats page. Is this a bug Google is working on? When will I be able to access my adsense account again?

Google's AdSensePro Stephanie confirmed the issue on February 25th, saying:

I've checked with our engineers and they've confirmed that this is an issue they're currently working to fix. I'll be sure to post another update when the issue is resolved. In the meantime, you might want to try a few attempts at logging in - some publishers who reported this issue were able to log in successfully after a few tries.

Later on February 29th, Friday, Google has finally confirmed that the issue was fixed. Stephanie said:

Our engineers have now resolved most of the issues you all reported -
please try the process again and let me know if you run in to any other problems while reviewing the new Terms.

However, fixing this issue, seemed to have caused another. AdSense publishers are reporting that the new Terms of Service have disappeared and they have "neither accepted nor declined" the new terms. I can confirm that I also have never accepted or declined the new terms of service and I can login directly to my reports.